A case-control study of white males over the age of 30 whose cause of death was brain or CNS cancer will be conducted in geographic areas with a heavy concentration of petroleum refining and chemical industries. The next-of-kin of cases and controls will be interviewed in person to obtain occupational histories and other information which may be pertinent to the origins of these cancers. Responsibilities of the Contractor as outlined in the Description of Work would include: identification of appropriate geographic study areas, selection of cases and matched controls from State Vital Statistics Offices, procurement of death certificates on cases/controls, development and use and NCI-approved interview questionnaire, review of case subject hospital records, training of interviewers, verification/editing/coding of all collected information, and delivery of an edited computer tape to NCI.